Search results for "cell culture"

Development of a novel in vitro system for biomedical applications

2022

Nella ricerca scientifica e medica, l'uso degli animali ha apportato notevoli benefici all’uomo. Sebbene la loro fisiologia non imiti perfettamente il corpo umano, essi agiscono come perfetti "modelli" per lo studio delle malattie umane e lo sviluppo di nuovi farmaci e trattamenti. Tuttavia, secondo la Food and Drug Administration (FDA), solo l'8% dei farmaci testati sugli animali è considerato sicuro ed efficace per l'uso sull’essere umano, il 92% non lo è. Questi tassi di fallimento estremamente elevati nello sviluppo di farmaci, insieme ai costi in forte aumento, hanno portato molti ricercatori a rivalutare il valore degli studi in vivo sugli animali. Questo è stato il motivo per cui, ne…

New Tripentone Analogs with Antiproliferative Activity

2017

Tripentones represent an interesting class of compounds due to their significant cytotoxicity against different human tumor cells in the submicro-nanomolar range. New tripentone analogs, in which a pyridine moiety replaces the thiophene ring originating the fused azaindole system endowed with anticancer activity viz 8H-thieno[2,3-b]pyrrolizinones, were efficiently synthesized in four steps with fair overall yields (34–57%). All tripentone derivatives were tested in the range of 0.1–100 μM for cytotoxicity against two human tumor cell lines, HCT-116 (human colorectal carcinoma) and MCF-7 (human breast cancer). The most active derivative, with GI50 values of 4.25 µM and 20.73 µM for HCT-116 a…

Cytotoxicity of 35 medicinal plants from Sudan towards sensitive and multidrug-resistant cancer cells

2015

Abstract Background Cancer is a complex disease with multiple genetic and epigenetic alterations. Since decades, the hallmark of cancer therapy is chemotherapy. Cytotoxic drugs erase rapidly dividing cells without sufficient differentiation between normal and cancerous cells resulting in severe side effects in normal tissues. Recently, strategies for cancer treatment focused on targeting specific proteins involved in tumor growth and progression. The present study was designed to investigate the cytotoxicity of 65 crude extracts from 35 Sudanese medicinal plants towards various cancer cell lines expressing molecular mechanisms of resistance towards classical chemotherapeutics (two ATP-bindi…

Cytotoxicity of the indole alkaloid reserpine from Rauwolfia serpentina against drug-resistant tumor cells.

2015

Abstract Background: The antihypertensive reserpine is an indole alkaloid from Rauwolfia serpentina and exerts also profound activity against cancer cells in vitro and in vivo. The present investigation was undertaken to investigate possible modes of action to explain its activity toward drug-resistant tumor cells. Material and methods: Sensitive and drug-resistant tumor cell lines overexpressing P-glycoprotein (ABCB1/MDR1), breast cancer resistance protein (ABCG2/BCRP), mutation-activated epidermal growth factor receptor (EGFR), wild-type and p53-knockout cells as well as the NCI panel of cell lines from different tumor origin were analyzed. Reserpine's cytotoxicity was investigated by res…

Selective downregulation of the MDR1 gene product in Caco-2 cells by stable transfection to prove its relevance in secretory drug transport.

2005

Considerable interest is focused on overcoming multidrug resistance (MDR) in cancer chemotherapy. The in vitro experiments to characterize P-glycoprotein's (P-gp) function and to decrease its effects have led to a variety of strategies such as addition of competitors or supplementation of the medium with oligonucleotides complementary to the 5'-end of the MDR1-mRNA. For the Caco-2 cell line, an in vitro model for absorption screening, expressing multiple transporters including P-gp, which pumps substances back into the apical solution, P-gp activity might mask other relevant transport proteins' activity. The objective of the present study was to construct a Caco-2 subline with reduced P-gp …

Metabolic shift of polyphosphate-accumulating organisms with different levels of polyphosphate storage

2012

Previous studies have shown that polyphosphate-accumulating organisms (PAOs) are able to behave as glycogen-accumulating organisms (GAOs) under different conditions. In this study we investigated the behavior of a culture enriched with Accumulibacter at different levels of polyphosphate (poly-P) storage. The results of stoichiometric ratios Gly degraded/HAc uptake, PHB synthesized/HAc uptake, PHV synthesized/HAc uptake and P release/HAc uptake confirmed a metabolic shift from PAO metabolism to GAO metabolism: PAOs with high poly-P content used the poly-P to obtain adenosine tri-phosphate (ATP), and glycogen (Gly) to obtain nicotinamide adenine dinucleotide (NADH) and some ATP. In a test whe…

Gene expression changes responsible for lapatinib acquired resistance in HER2 positive gastric cancer cell lines: a microarray analysis

2017

Abnormal Marker Expression in Acute Leukemia (AL) Characterized by Monoclonal Antibodies and Flow Cytometry

1987

The application of refined immunologic and enzymatic markers to conventional morphologic and cytochemical techniques has revealed an unexpected heterogeneitiy in acute leukemia (AL). Since the development of monoclonal antibodies (MoAbs) to lineage specific differentiation markers, there have been several reports of AL patients whose blast cells represent relatively homogeneous populations with phenotypic features of more than one cell line [1–5] or are characterized by the coexistence of separate cell populations each demonstrating either lymphoid or myeloid features [6–10].

Arsenic Trioxide Abrogate MN1 Mediated RA-Resistance in Acute Promyelocytic Leukemia

2019

Introduction: Described as a well know marker of worse prognosis in acute myeloid leukemia (AML), MN1 overexpression has been associated with inv(16) or EVI1 overexpression (Heuser et al., Blood 2007). The promoter region of the MN1 gene has Retinoic Acid Response Elements (RAREs), and higher levels of MN1 expression have been associated with decreased response to retinoic acid (RA) in vitro. Nevertheless, in the context of acute promyelocytic leukemia, little is known about MN1 gene expression and functionality in vivo. Aims: Here, we investigated the effects of in vitro treatment with RA plus arsenic trioxide (ATO) in APL cell lines and primary blasts overexpressing MN1. Additionally, we …

Pituispheres Contain Genetic Variants Characteristic to Pituitary Adenoma Tumor Tissue

2020

The most common type of pituitary neoplasms is benign pituitary adenoma (PA). Clinically significant PAs affect around 0.1% of the population. Currently, there is no established human PA cell culture available and when PA tumor cells are cultured they form two distinct types depending on culturing conditions either free-floating aggregates also known as pituispheres or cells adhering to the surface of cell plates and displaying mesenchymal stem-like properties. The aim of this study was to trace the origin of sphere-forming and adherent pituitary cell cultures and characterize the potential use of these surgery derived cell lines as PA model. We carried out a paired-end exome sequencing of …